The present invention relates to a pump apparatus for supplying a working fluid to a vehicular steering apparatus and a control method for controlling the pump apparatus.
Japanese Patent Application Unexamined Publication No. 2007-92761 discloses a variable displacement pump for use in a steering apparatus for vehicles. The variable displacement pump of this conventional art includes a control valve which controls a cam ring, and a solenoid which operates and controls the control valve. The variable displacement pump is constructed to increase a discharge quantity when a steering operation is executed, and reduce the discharge quantity when the steering operation is not executed. The thus constructed variable displacement pump aims to enhance a steering performance and reduce a pump load.